For example, one of fuel cell stacks known in the art is described in Patent Document 1. The fuel cell stack described in Patent Document 1 includes a multicell module that is formed by stacking a plurality of single cells each including a membrane electrode assembly and a pair of separators holding the membrane electrode assembly therebetween. Each of the cells includes a non-power generating area and manifolds that are disposed in the non-power generating area to flow respective fluids of coolant, combustion gas and oxidation gas. In the fuel cell stack, a plurality of multicell modules are arranged in series in the cell stacking direction, and the gaps between the multicell modules are sealed with bead gaskets.